1. Field of the Invention
The present invention relates to the provision of emergency services, such as fire fighting, policing, military services and special operations. More specifically, the invention relates to providing location information for emergency service workers and for others who may be coordinating emergency service operations. Although the present invention will mainly be described in terms of fire fighting operations, it applies generally to many different types of emergency service operations.
2. Description of the Related Art
It can be challenging to determine the location of emergency service providers during an emergency service operation. For example, when fire fighters are in a building, they are generally not familiar with the layout of the building and may become disoriented. If the building is burning, smoke may make it difficult for a fire fighter to see clearly enough to distinguish the features of the building. Moreover, these features will change if parts of the building are consumed by fire.
Global Positioning System (“GPS”) devices can be very useful for location and navigation, and therefore have become very popular in recent years. In years past, GPS devices would provide only a determination and display of X/Y or latitude/longitude information. This required a user to have a map and to be able to determine the user's position on the map according to the X/Y or latitude/longitude information. Moreover, the accuracy of a commercially available GPS device provided only a rough idea of a person's location, e.g., within approximately 100 meters.
GPS devices now provide greater accuracy and many are now provisioned with cartographic data. Such devices automatically provide a map display with the user's location indicated on the display. However, GPS devices still do not provide location information that is sufficiently accurate to navigate inside a building.
In addition, GPS devices do not provide displays of building layouts with a user's position indicated on the display. Moreover, GPS devices often do not function inside buildings. Under emergency conditions of fire, flood, earthquake, military operations, etc., there may be further disruption of GPS reception.
It may also be difficult to determine who was within a building prior to an emergency and who may still be in harm's way as the emergency unfolds. Even if it is known that certain people are still inside a building and need to be rescued, it can be difficult to locate these victims. During a fire victims may be unable to provide their location (e.g. via cellular telephone) because they are disoriented or have lost consciousness.
It would be desirable to locate emergency service providers and victims accurately and reliably during emergency operations, particularly when the emergency service providers and victims are within buildings.